<template>
  <!-- 二级分类页面 -->
  <div class='sub-category'>
    <div class="container">
      <!-- 面包屑 -->
      <SubBread />
      <!-- 筛选区 -->
      <SubFilter @filter-change="changeFilter" />
      <!-- 结果区域 -->
      <div class="goods-list">
        <!-- 排序 -->
        <SubSort @sort-change="changeSort" />
        <!-- 列表 -->
        <ul>
          <li v-for="item in goodsList" :key="item.id">
            <GoodsItem :goods="item" />
          </li>
        </ul>
        <!-- 加载 -->
        <XtxInfiniteLoading :loading="loading" :finished="finished" @infinite="getData" />
      </div>
    </div>
  </div>
</template>

<script setup>
import SubBread from './components/sub-bread'
import SubFilter from './components/sub-filter'
import SubSort from './components/sub-sort.vue'
import GoodsItem from './components/goods-item'
import { ref, watch } from 'vue'
import { findSubCategoryGoods } from '@/api/category'
import { useRoute } from 'vue-router'
// 1. 基础布局
// 2. 无限加载组件
// 3. 动态加载数据且渲染
// 4. 任何筛选条件变化需要更新列表
const route = useRoute()

const loading = ref(false)
const finished = ref(false)
const goodsList = ref([])
// 查询参数
let reqParams = {
  page: 1,
  pageSize: 20
}
// 获取数据函数
const getData = () => {
  loading.value = true
  // 设置二级分类的ID
  reqParams.categoryId = route.params.id
  findSubCategoryGoods(reqParams).then(({ result }) => {
    // 获取数据成功
    if (result.items.length) {
      // 有数据就追加数据
      goodsList.value.push(...result.items)
      // 把page改成下一页页码
      reqParams.page++
    } else {
      // 没有数据，代表加载完成
      finished.value = true
    }
    loading.value = false
  })
}

// 在更改了二级分类的时候需要重新加载数据
watch(() => route.params.id, (newVal) => {
  if (newVal && route.path === `/category/sub/${newVal}`) {
    goodsList.value = []
    reqParams = {
      page: 1,
      pageSize: 20
    }
    finished.value = false
  }
})

// 监听筛选区改变
const changeFilter = (filterParams) => {
  reqParams = { ...reqParams, ...filterParams }
  reqParams.page = 1
  goodsList.value = []
  finished.value = false
}
// 监听排序改变
const changeSort = (sortParams) => {
  reqParams = { ...reqParams, ...sortParams }
  reqParams.page = 1
  goodsList.value = []
  finished.value = false
  getData()
}
</script>

<style scoped lang='less'>
.goods-list {
  background: #fff;
  padding: 0 25px;
  margin-top: 25px;

  ul {
    display: flex;
    flex-wrap: wrap;
    padding: 0 5px;

    li {
      margin-right: 20px;
      margin-bottom: 20px;

      &:nth-child(5n) {
        margin-right: 0;
      }
    }
  }
}
</style>
